SCN5A and carcinoma: Given that ESL prolongs the PR interval (Vaz-Da-Silva et al., 2012), potentially via inhibiting the cardiac Nav1.5 isoform, together with the interest in inhibiting Nav1.5 in carcinoma cells to reduce invasion and metastasis (Driffort et al., 2014; Martin et al., 2015; Nelson et al., 2015b; Elajnaf et al., 2018; Djamgoz et al., 2019), it is also relevant to evaluate the electrophysiological effects of ESL and S-Lic on this isoform.